<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="./css/base.css">
    <style>
        .w {
            width: 1200px;
            height: 6000px;
            margin: auto;
            background-color: palegreen;
        }

        .sub-nav {
            position: fixed;
            left: 50%;
            top: 50%;
            width: 48px;
            margin-left: 610px;
            /* 最小高度 */
            min-height: 92px;
            background-color: pink;
        }

        .sub-nav img {
            width: 100%;
        }

        .sub-nav li {
            overflow: hidden;
            position: relative;
            margin-bottom: 1px;
        }

        .sub-nav li span {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: seagreen;
            color: #fff;
            text-align: center;
            /* 将盒子的中心点设置为左下角 */
            transform-origin: left bottom;
            /* 设置对应的旋转角度 */
            transform: rotate(180deg);
            /* 添加过渡动画 */
            transition: all .8s;

        }

        /* 鼠标经过li的时候让span从180deg切到0deg */
        .sub-nav li:hover span {
            transform: rotate(0deg);
        }

        .sub-nav li:nth-child(1) span,
        .sub-nav li:nth-child(2) span {
            line-height: 92px;
        }
    </style>
</head>

<body>
    <div class="sub-nav">
        <ul>
            <li>
                <img src="./img/01.png" alt="">
                <span>辟谣</span>
            </li>
            <li>
                <img src="./img/01.png" alt="">
                <span>举报</span>
            </li>
        </ul>
    </div>
    <div class="w"></div>
</body>

</html>